Does How To Not Summon A Demon Lord Mature Anime Have An OVA?

Lyon Aschere, well-known as "The Reaper" is the youngest person to be an official Royal Knight of Avaritia and is also the personal Knight of King Charles Avaritia II eldest daughter Princess Jiniya Avaritia. But with him being a lowly commoner with high aptitude for magic and martial arts his status as a Royal Knight was hidden from the public. A few weeks after being appointed as a royal knight his left eye began to ache, showing him disturbing images, thinking that it was only a matter of hallucinations he disregarded it. Until the Princess found out about his problem, the princess being kind to her childhood friend, decides to help him figure out what is happening to his eye, venturing out to different Kingdoms looking for answers. But to their surprise the world was riddled with secrets that dated back from thousands of years. The story follows Lyon and Jiniya as they try to understand what powers lie behind Lyon's eye.

Arianna had not planned on using magic to summon anything, she just wanted to get out of an arranged marriage. She was told of the ancient magic of summoning a guardian but instead she had summoned a demon—the demon king himself. But what would he ask in return for his loyalty to this princess?

Serra is a normal senior high school student who works really hard every night and weekend to pay off her parents' debts from loan sharks. But when she couldn't keep up with payments anymore, she decided to end her life. Surprisingly, she woke up in a different light-- in another world. What's more shocking was when she is addressed by one of the people as the demon king's bride.

A normal girl just as usual working every day. This changed when she met a demon. She made a contract with the demon to help her. She just want to use her demon, but she find that she can't help fall in love with the Demon

In an attempt to summon a strong familiar, Rubisviel Fyaril, Witch of The Dark Forest, created a spell to bring forth an otherworldly entity only to end up summoning a Demon Prince with no memories of his past. She managed to convince the demon to leave however they parted after he gave her an oddly familiar kiss. When she finally thought that her life was going back to its witchy normality, her visitor returned only to claim that he's going to reside with her due to a master-servant curse that bound them on his summoning. Ruby was forced to live with a very flirtatious demon who seemed to want to bed her so she tried finding a way to break their curse. But what if his presence only attracts trouble? And what if he's actually part of the past she wanted to forget? Watch out little witch you're not the only one brewing evil in her pot. A Demon Queen you've once vanquished is rising from her grave to get back to you and when she does you better sharpen your weapons and kiss your demon for the long nights about to come.

Daemon who was once a useless, powerless man despised and bullied by others, worked his way to the top, facing many challenges and opposition from crooked and twisted ministers, sinister and wicked demon Lords who are trying to bring him down, becoming the Demon Emperor, a figure who now holds the highest authority. He swore revenge against the humans - the ones who ruin his family, massacred his innocent family and left him orphan. There's a big organisation called the Demon Hunters whose aim is to rid the world of demons, and they were the ones who killed Daemon's family. Amidst the chaos, he encounters Victoria Bennett, an unsuspecting human who stumbles into his realm searching for her missing brother, igniting a forbidden romance between two souls from opposing worlds. However, their love faces insurmountable obstacles as both humans and Victoria's own family relentlessly strive to tear them apart. Will Daemon and his loyal Demon Lords succeed in their audacious mission? Can they find solace in one another, despite the deceit and dark enigmas they harbor? Can the flame of love burn brightly between a human and a demon, defying the shackles of an ancient curse that has endured for countless millennia? And in the ultimate test of devotion, what choice will Victoria make: her blood ties or the irrevocable love of her life?